Electrical connector



Feb- .25 1947 J. M. VAN VLEET BLBQTRICAL CQHHBCTOR rma Nov. 29. 1945 v f ...u

lthreads of the nut .Patented Feb. 25, 1947 2,416,423 ELECTRICAL CONNECTOR John M. Van Vleet,

to Kyle Corporation,

Wauwatosa, Wis., assignor South Milwaukee, Wis.,

a corporation of Wisconsin Application November 29, 1943,

Serial No. 512,137

4 Claims. (Cl- .Z4-243) y This invention relates to electrical connectors and is particularly directed to the type of electrical connector in which a bifurcated bolt is employed and adapted to receive the electrical conductors between the spaced arms of the bolt,

and in which a sliding plunger is urged to clamp` the conductors by means of a nut screwed on the bolt and coacting withthe sliding plunger. In the connectors as heretofore constructed of this general type it has been the practice to use V-threads. It has been found that with the heretofore known types of connectorsthe reaction between the threads of the-bolt and the when the nut is tightened produces resultant forces which tend to move the spaced arms of the bolt towards each other into binding engagement with the sliding plunger so that a considerable portion of the force exerted by the nut was needed to overcome the enormous friction between the arms and the plunger, this friction increasing as the ditionally it was found in connectors as heretofore constructed that the effective area of contact between the threads of the nut and bolt decreased as the nut was tightened due to the inward motion of the spaced arms of the bolt and frequently the area of contact became so small that the threads stripped. v

This invention is designed to overcome the above noted defects, and objects oLthis invention are to provide an electrical connector employing abifurcated bolt with spaced arms and a sliding plunger therebetween and a nut threaded on the bolt and coacting with the plunger, in which the coacting faces of-the threads of the nut and the bolt which transmit the force from the nut to the bolt are so arranged that no resultant forces are produced tending to force the spaced arms of the bolt into binding engagement with the sliding plunger, to thereby avoid binding between the-sliding plunger and the spaced arms of the bolt, and to maintain the effective area of contact b'etween the threads of the nut and the threads of the bolt at least the same as it was before the nut was tightened.

Further objects of this invention are to provide an electrical connector as deiined hereinabove in which the threads are undercut to provide coacting slanting faces which have a tendency to draw the spaced arms of the bolt apart and thereby not only guard against any chance of binding between the spaced arms and the sliding plunger but also cause a wedging and interlocking between the threads of the bolt and the threads of the nut, to thus lock the nut against bolt is tightened. Ad-

inadvertent loosening uponiarring which would result in burning the electrical conductors normally clamped by the connector.

An embodiment of the invention is shown in the accompanying drawing, in which:

Figure 1 is a view of the connector ing position.

Figure 2 is a with the conductors shown in section. y

Figure 3 is a sectional view von the line -I of Figure A2.

Figure 4 is a sectional view drawn to an enlarged scale on the line 4--4 of Figure 3.

Figure 5 is a viewshowing the nut and sliding plunger detached from the bolt, the nut being shown in section corresponding to asection onl the line 5--5 of Figure 3. Referring to the drawings, it will be seen that the connector comprises a bifurcated bolt l which zo is provided with a pair of arms 2 and with a hexagonal or other polygonal-shaped head 3.

the arms which is freely slidable between the arms I. y 25, The plunger is provided with a head 5 which has a V-shaped channel thereacross as indicated at 8. The sliding plunger 4 is provided with outwardly projecting shouldered portions 1 against which the nut 8 bears. The nut is prevented from separating from the sliding plunger by means of a pair of ears 9 struck or sheared outwardly from the shank I of the plunger. 'I'he nutis threaded on the bolt and is adapted to force the plunger inwardly, thereby clamping the conductors l0 and Il in tight engagement with each other and with the head and plunger of the connector, thus securing a rm and excellent electrical connection.

In applying the connector the nut is unscrewed from the bolt, thus carrying with it the sliding plunger, and the arms of the bifurcated bolt are positioned over the conductors. Thereafter the plunger is inserted between the arms 2 of thebolt and the nut is screwed onto the bolt. i

In connectors as heretofore made V-shaped threads were employed and when the nut was tightened, it resulted in forcing the `arms of the bifurcated bolt towards each other into tight binding engagement with the sliding plunger. When it was attempted to tighten the nut, the clamping action between the arms and the plunger was increased very much to the detriment of the correct functioning of the connector.

A very important phase of this invention is in providing inwardly cut or overhanging threads in eindpside elevation of the connector A sliding plunger 4 is normally positioned betweenr` 2 and comprises a shank portion y4' 3 on the bolt and nut as shown most clearly in Figure 4. It is to be noted that the threads I2 of the bolt and I3 of the nut are undercut so that conductors placed between the spaced arms, the

their faces slant as indicated in Figure 4. When the nut 8 is tightened, there are resultant forces produced which tend to move the arms 2 outwardly instead of inwardly,.thus spreading the arms apart and thus preventing the arms 2 from binding against the sliding plunger. The sliding plunger 4 is therefore freely slidable between the arms under all conditions, no matter how tightly the nut is tightened.

In addition to the above advantage another very important advantage resides in the fact that as the nut is tightened, as will be apparent from Figure 4,`there is a tendency to move the armsr 2 outwardly and tok force the undercut threads I2 of the bolt into binding or wedging engagement.

with the undercut'threads I3 ofthe nut, lthat is to say, .the undercut threads of the bolt tend to move inwardly into the grooves in the nut and thus tend to lock the nut and bolt together and prevent loosening of the nut from jarring.

It is to be noted that there is a clearance be-y tween the tip of the threads oi' the nut and the bottom of the grooves in the bolt and also a clearance between the tip of the threads of the bolt and the bottom oi the grooves in the nut. An examination of Figure 4 shows that the threads of the bolt and nut are tapered in cross-section and when it is considered that these tapered threads are forced into tapered grooves, it is apparentthat an interlocking occurs.

It is preferable to make the bolt, the plunger and the nut of. material having good electrical conducting qualities.

It will be seen that a novel form of connector has been provided by this invention in whicha bifurcated bolt is employed in conjunction with a sliding plunger and a nut and in which the parts are so organized that there is no tendency to bind the sliding plunger between the arms of the bifurcated bolt on the one hand and also so that there is an interlocking action between the` bolt and nut which tends to lock the nut against inadvertent loosening under jarring. It is to be further noted that the effective area of contact between the threads of the bolt and the threads of the nut does not decrease when the nut is tightened. In reality there is a small increase in effective area. Inasmuch as there is no decrease f in effective area of contact between the threads, the tendency to strip the threads due to a decrease of eective area is avoided.

It will be seen further that the connector is of very simple construction and is easy to produce.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

Iclaim:

1. A connector for connecting electrical conductors comprising a bifurcated threaded bolt l having a pair of spaced arms adapted to receive conductors therebetween and a head portion joining said spaced arms at one end, a sliding plunger slidable between said spaced arms, and a threaded nut coacting with said bolt and operatively en-A l gaging said sliding plunger to force said sliding 3 plunger into clamping relation to the electrical threads of said bolt and the threads of said nut having slantingfaces coacting-when said nut is tightened to produce resultant forces tending to spread said spaced arms apart, whereby binding between said sliding plunger and said spaced arms is avoided.

2. A connector for connecting electrical conductors comprising a bifurcated threaded bolt having a. pair of spaced arms adapted to receive conductors therebetween and a head portion joining said spaced arms at one end, a sliding plunger slidable between said spaced arms, and a threaded nut coacting with said bolt and operatively engaging said sliding plunger to force said sliding plunger into clamping relation to the electrical conductors 'placed between the spaced arms, the threads of said bolt and the threads of said nut having undercut slanting faces coacting when said nut is tightened to produce resultant forces tending to spread said spaced arms apart,

whereby binding between said sliding plunger and said spaced arms is avoided.

3. A connector for connecting electrical conductors comprising a bifurcated threaded bolt having a pair of spaced arms adapted to receive conductors therebetween and a head portion joinlng said spaced arms at one end, a sliding plunger slidable between said spaced arms, and a threaded nut coacting with said bolt and operatively engaging said sliding plunger to force said sliding plunger into clamping relation to the electrical conductors placed between thel spaced arms, the threads of said bolt and the threads of said nut having undercut slanting faces coacting when said nut is tightened to produce resultant forces tending to spread said spaced arms apart and causing wedging between the threads of said bolt and nut to prevent loosening of said nut and to i of said nut having undercut slanting faces ooactl ing when said nut is tightened to produce resultant forces tending to spread said spaced arms apart and causing wedging between the threads of said bolt and nut to prevent loosening of said nut and to prevent binding of said spaced arms against said plunger, the outer tip of the threads of said bolt and nut being spacedfrom the bottom of the grooves of said nut and bolt. respectively.

JOHN M. VAN VLEET.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,943,677 Kearney Jan. 16, 1934 2,088,481 Mylius July 27. 1937 

